Sequences of nuclear-encoded small-subunit rRNA genes have been determined for representatives of the enigmatic genera Dermocystidium, Ichthyophonus, and Psorospermium, protistan parasites of fish and crustaceans. The small-subunit rRNA genes from these parasites and from the "rosette agent&quo...

This review critically examines information on structure and developmental cycles, systematics and diagnosis, techniques, pathogenesis of infection, immunological responses, epidemiology, control and directions for future research on species of Sarcocystis in man, livestock, wildlife and other hosts...

A tetrazolium-based cytotoxicity assay was modified to determine the anti-protozoal activity of compounds towards the lobster parasite A. haemophila. To obtain reproducible results, A. haemophila maintained in continuous culture were preferable to freshly isolated A. haemophila. It was also found th...

Meronts, merozoites, oocysts and unidentified stages of a new species of Eimeriidae were found in the reproductive tract of one of 4 C. canadensis nelsoni bulls shot at the beginning of the rut season in Saskatchewan, Canada. The eimeriids were seen free in the luminal content and, on one occasion o...

The early endogenous development of S. rauschorum in D. richardsoni was studied. After determining the dose-response effects of sporocysts of S. rauschorum on lemmings (doses greater than 500 sporocysts were lethal during hepatic merogony), sporocysts were administered to additional lemmings that we...

I. brachyrhynchi were recovered from faeces of experimentally infected juvenile crows (Corvus brachyrhynchos) and stored for up to 12 months in a 2.5% (w/v) solution of potassium dichromate at 4 degrees C. Sporocysts were released from the oocysts by grinding in a homogenizer. Various bile salts, ta...

Although 1993 landings of lobsters were valued at $300 million in Canada and $210 million in the United States, postharvest losses are 10-15% annually. "Bumper car" disease of lobsters caused by the scuticociliate Anophryoides haemophila, can be significant in coldwater impoundments. Altho...

In May 1989 a previously unidentified apicomplexan parasite was found in brookstock bay scallops Argopecten irradians from the east coast of Canada. Host tissue responses ranged from focal hemocytic encapsulation to the formation of abscesses containing necrotic hemocytes, parasites and ceroid. Bay ...

Developmental stages of Cryptosporidium sp. (Protozoa: Cryptosporiidae) were observed in tracheal epithelium of two groups of turkey poults from a farm in central Saskatchewan. Lesions associated with the parasite included excess mucus, epithelial hyperplasia and metaplasia and necrosis, and macroph...

Between 1980 and 1982 the kidneys of 627 waterfowl from Saskatchewan, Canada, were examined for oocysts by a modified flotation technique. Eimeria spp. were detected in 136 of 289 ducks (11 of 12 species), 130 of 287 geese (2 species) and 2 of 4 whistling swans (Cygnus columbianus). Bucephala clangu...

Besnoitia sp. was diagnosed in two caribou (Rangifer tarandus caribou) which died of pneumonia at the Assiniboine Park Zoo (Winnipeg, Manitoba, Canada) in 1983. During the following 3 yr besnoitiosis spread to an isolated herd of caribou, to mule deer (Odocoileus hemionus hemionus) and to reindeer (...

Muscle containing macroscopic cysts of Sarcocystis sp. from naturally infected wild shoveler (Anas clypeata) ducks was fed to two captive striped skunks (Mephitis mephitis). The skunks passed sporocysts in their feces beginning 19 and 22 days post-infection, and continued to pass small numbers of sp...

Crows were intubated with varying doses of sporulated oocysts of I. brachyrhynchi n.sp. from a naturally infected crow, and killed for necropsy at various hours postinoculation. Tissues were fixed in Bouin's fluid and processed for light microscopy. Sporulation of I. brachyrhynchi to typical isospor...

A comparison of the coinfection of bay scallops with Perkinsus karlssoni and an as yet unidentified coccidian is described. P. karlssoni occurred in a range of host tissues including mantle, digestive gland, intestine, gill and gonad. Host tissue response elicited against P. karlssoni ranged from fo...

The etiological agent of 'bumper car' disease in lobsters Homarus americanus is described as a new species of ciliate, Anophryoides haemophila (Scuticociliatida: Orchitophryidae). A. haemophila n. sp. is distinguished from other species in the genus by the curved rectangular oral polykinetid 2, a so...